The Spirochetes (1)

Characteristics: Gram negative; flexible; helical; have periplasmic flagella; saprophytes or paracytes.

Family 1: SPIROCHAETACEAE

Genus 1: Spirochaeta

The genus Spirochaeta represents a group of free-living, saccharolytic non-pathogenic, obligate or facultative anaerobic helical shaped bacteria. Isolated strains have been obtained from a variety of freshwaters and marine waters. Extremophilic species include anaerobic, thermophilic isolated form hot springs in New Zealand, the moderately thermophilic Spirochaeta caldaria from cyanobacterial mats of hot springs in Utah and Oregon and the extremely thermophilic Spirochaeta thermophila from marine areas in Shiaskotan Island in Russia. There are also alkaliphilic spirochetes such as S. alkalica, S. africana, S. asiaticaisolated from the alkaline Lake Magadi in Kenya and from sulfide-saturated mud sediments of Lake Khatyn in Siberia (Hoover et al, 2003).

In addition, culture-independent studies revealed the presence of Spirochaeta species in other environments such as anaerobic bioreactors, and the digestive tract of termites (Drone et al, 2003). A number of members of the genus Spirochaeta inhabit extreme environments with respect to temperature, salinity, and pressure . These microorganisms may hence harbor enzymes with potential biotechnological applications (Leschine et al, 2006).

  A cell of Spirochaeta zuelzerae. These morphologically distinct prokaryotes are also phylogenetically distinct

        

Habitat: Harmless inhabitants of water, mud, and sediments of marine and freshwater environments.

Oxygen Relationships: Anaerobic and facultatively anaerobic

Major character: Use carbohydrates but not amino acids as carbon and energy source.

Species: 

1. Spirochaeta africana
2. Spirochaeta alkalica
3. Spirochaeta americana
4. Spirochaeta asiatica
5. Spirochaeta aurantia
6. Spirochaeta bajacaliforniensis
7. Spirochaeta caldaria
8. Spirochaeta coccoides
9. Spirochaeta halophila
10. Spirochaeta isovalerica
11. Spirochaeta litoralis
12. Spirochaeta smaragdinae
13. Spirochaeta stenostrepta
14. Spirochaeta taiwanensis
15. Spirochaeta thermophila
16. Spirochaeta xylanolyticus
17. Spirochaeta zuelzerae

Applications: Harbor enzymes with potential biotechnological applications.

Colony of Spirochaeta (Uruguay, 1999)